This dataset contains the ToF-SIMS data for Figure 6 of "Interlaboratory comparison of XRF analysis on thin films, including alloys, oxides, multilayers, and a lithium-ion battery material". The ToF-SIMS data for Figure 6, contained in the two files TOFSIMS1.txt and TOFSIMS2.txt, has 14 columns each. These are seperated by whitespace. The file TOFSIMS2.txt contains data for the left part of the figure, i.e. the initial measurment, and TOFSIMS1.txt contains data for the right part of the figure, i.e. after 9 months storage. The first column of each file corresponds to the sputter time in seconds. The rest of the columns correspond to the background-corrected intensity in a.u. for the following ions in that order: Co+, Si+, Al+, Na+, K+, Ca+, Fe+, N+, C+, Cu+, Co2+, B+, Ti+, C+